Valve has officially announced today the first downloadable content for its puzzle-platform hit Portal 2. The add-on will feature "new test chambers for players, leaderboards, challenge mode for single and multiplayer modes, and more."

The announcement comes after a recent statement by Valve Director of Marketing Doug Lombardi. Speaking in an interview with Fast Company, Lombardi said more details would be revealed over the coming weeks. "We will be announcing some DLC for it, so folks can keep a look out for more content coming this summer. We'll be putting more details out about that in a week or so. We'll support that with more videos or more comics."

According to the Valve press release, Portal 2 DLC #1 is currently in development and is slated to be released this coming summer. In a move that is sure to delight players, the downloadable content will be offered free of charge for the Xbox 360, PlayStation 3, PC and Mac.

"Portal 2 was released April 19 and currently holds a Metacritic score of 95%, making it the top rated multiplatform game of 2011. Portal also captured the number 1 chart position in the UK, Germany, and the Nordic countries during its first week of availability, making it the fastest-selling Valve release since Half-Life 2."

"A hilariously mind-bending adventure that challenges you to use wits over weaponry in a funhouse of diabolical science, Portal 2 features expansive single and cooperative multiplayer game modes."